The table below shows how much money a grocery store receives for selling different amounts of asparagus.
asparagus sales
number of pounds
total sales
4 lb=
$10
6 lb=
$15
8 lb=
$20
10 lb=
?
12 lb =
?
if the unit rate is constant, what are the total sales for 12 pounds of asparagus?
a $22.50
b $25.00
c $30.00
d $32.50